1. Field of the Invention
The present invention relates to an electrical connector, and more particularly to an electrical connector that is easily manufactured, mounts stably to a substrate, and provides a high contact density for a given area on the substrate.
2. Description of the Prior Art
Conventional electrical connectors include complementary male and female connectors for forming electrical connections between two substrates. An electrical connection is established when the male connector is received by the female connector. For example, computers and other electrical equipment include electrical connectors for connecting printed circuit boards, for connecting a printed circuit board to a backplane, and/or for connecting a printed circuit board to a cable. Electrical connectors may be mounted to a substrate in a vertical orientation or in an edge or right-angle orientation. In the vertical orientation, the electrical connection is established vertically or toward the surface of the substrate. Connectors that mount in an edge or right-angle orientation are often referred to as edge connectors. As the name implies, edge connectors mount to the edge of a substrate and often include contact elements bent in a right angle. Edge connectors establish an electrical connection horizontally or parallel to the substrate surface.
An example of a conventional electrical connector is shown in U.S. Pat. No. 4,274,700 to Keglewitsch et al. FIGS. 1-3 of U.S. Pat. No. 4,274,700 show a vertical female electrical connector having a female connector housing for mounting to a printed circuit board. FIGS. 4 and 5 of U.S. Pat. No. 4,274,700 illustrate a vertical male electrical connector having a male connector housing. As shown in FIGS. 2, 3, and 5 of U.S. Pat. No. 4,274,700, for example, the male and female connector housings each include a pair of fastening flanges extending outwardly from opposite ends of the main housing body. The fastening flanges may include apertures for receiving screws or rivets for securing the housing to the printed circuit board, as shown in FIG. 3. Alternatively, as shown in FIGS. 2 and 5 of U.S. Pat. No. 4,274,700, snap connectors may extend from the bottom surface of the fastening flanges. The snap connectors contract to fit through apertures formed in the printed circuit board and then expand to hold the housing to the printed circuit board. In either case, the apertures or snap connectors are aligned with a longitudinal axis of the connector housing.
Several problems exist with the electrical connector disclosed in U.S. Pat. No. 4,274,700 and similar connectors. For example, stresses applied to the male and female contacts adversely affect the electrical connection between the printed circuit boards. The stresses may cause the male and female contacts to bend, break, or otherwise become misaligned or damaged, whether immediately or in time. The stresses may further damage the electrical connection between the male or female contacts and the printed circuit board to which they are mounted. The problem of stresses on the male and female contacts originates from several sources, a few of which are discussed below. Because the screws, rivets, snap connectors, or other fasteners are aligned with the longitudinal axis of the connector housing, the connector housing tends to rock or pivot on the printed circuit board along the longitudinal axis. In addition, rocking may occur between the male connector housing and the female connector housing during or after mating. Further, as shown in FIG. 7 of U.S. Pat. No. 4,274,700, the male and female contacts support at least a portion of the load of the male connector on the female connector.
While electronic devices have become smaller, the number of connections between printed circuit boards within the electronic devices has increased. Consequently, space on printed circuit boards has become increasingly valuable and should be conserved. Conventional electrical connectors, such as those shown in U.S. Pat. No. 4,274,700, for example, waste space on the printed circuit board.
Conventional edge connectors suffer from the same problems as conventional vertical connectors. FIGS. 1A and 1B illustrate two views of a conventional edge connector 10 fastened to a printed circuit board 20. The edge connector shown in FIGS. 1A and 1B is similar to the edge connector described in U.S. Pat. No. 5,575,688 to Stanford W. Crane, Jr. As shown, conventional edge connector 10 includes a housing 15 mounted to the printed circuit board 20 by screws 16, 17. Similar to the arrangement in U.S. Pat. No. 4,274,700, screws 16, 17 are aligned parallel to the longitudinal axis of edge connector 10. As indicated by the arrow in FIG. 1A, edge connector 10 may rock or pivot with respect to the surface of the printed circuit board 20. While not specifically shown in the drawings, edge connector 10 may also pivot or rock with respect to a corresponding connector. Further, edge connector 10 includes contacts that bear at least some of the connector load when mated. Edge connector 10 also wastes space on the printed circuit board.
Some conventional electrical connectors include fixed polarization features that permit mating in only one orientation. Such fixed polarization features are difficult for a user to identify. As a consequence, the user often attempts to force a connection while the connecters are not properly oriented. When the connection cannot be made, the user re-orients the connectors and tries again to force a connection. The contacts may be damaged when mating is attempted while the connectors are not properly oriented. In addition, such fixed polarization features are not suitable to applications where flexibility is required. Accordingly, there is a need for an improved polarization feature that is more readily identifiable to a user and/or that may be used in a variety of applications. There is also a need to protect the contacts in the event of mismating.
Accordingly, there is a need in the art to provide an electrical connector that is not subject to the deficiencies of conventional electrical connectors.
The present invention has been made in view of the above circumstances and has as an object to provide an electrical connector that stably mounts to a substrate.
A further object of the present invention is to provide an electrical connector that conserves area on the substrate and achieves a high density of electrical contacts in a given area of the substrate and/or length along the substrate.
A further object of the invention is to provide an electrical connector that provides a positive stop for another connector when mated, so that the contact pins of the electrical connector do not support the load of the other connector.
A further object of the invention is to provide an electrical connector that, when mated with another connector, prevents rocking with respect to that other connector.
A further object of the invention is to provide an electrical connector having a polarization feature that is easily identified by a user and that prevents damage to the contact pins in the event of mismatch.
A further object of the invention is to provide an electrical connector having a polarization feature that is replaceable.
A further object of the invention is to provide an electrical connector that may be easily manufactured with a variable number of contact pins.
A further object of the invention is to provide an electrical connector having any combination of the above objects.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
To achieve the objects and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention comprises an electrical connector for mounting to a substrate including an insulative connector housing and a plurality of contact pins held in the insulative connector housing. The housing has a first side, a second side opposite the first side, a first end, and a second end opposite the first end. The first and second ends include first and second hold-down tabs, respectively, for mounting the insulative connector housing to a substrate. The first hold-down tab is located proximal the first side and the second hold-down tab is located proximal the second side such that the first and second hold-down tabs are diagonal.
To further achieve the objects and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention further comprises an electrical connector assembly including a male connector and a female connector. The male connector includes a male connector housing and a plurality of male contact pins held in the male connector housing in at least one row. The male connector housing has first and second staggered mounting extensions for mounting the male connector housing to a first substrate. The female connector includes a female connector housing and a plurality of female contact pins held in the female connector housing in at least one row. The female connector housing has first and second staggered mounting extensions for mounting the female connector housing to a side of a second substrate. At least a portion of the male connector is received within the female connector such that the male contact pins contact the female contact pins to establish an electrical connection therebetween.
The present invention further comprises apparatus for permitting mating of first and second electrical connectors in a single orientation embodied by structure including a polarization cap adapted for detachable connection to a face of the first electrical connector. The polarization cap includes one or more polarization features and a plurality of holes configured for receiving electrical contacts of the second electrical connector for contacting electrical contacts of the first electrical connector.
The present invention further comprises an electrical connector for mounting to a substrate and having an insulative mounting element having a first face and a second face, a plurality of contact pins having a contact portion and a tail portion, and a polarization cap detachably connected to said insulative mounting element to cover at least a portion of the first face. The contact pins are held in the insulative mounting element such that the contact portions extend from the first face and the tail portions extend from the second face. The polarization cap has at least one polarization feature and a plurality of openings for permitting access to the contact portions of the contact pins.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.